Use of saliva flow rate measurement in minor salivary glands autotransplantation for treatment of severe dry eye disease

AIMS: To use minor salivary glands’ flow rate (MSGFR) measurement in minor salivary glands (MSGs) autotransplantation for the treatment of severe dry eye disease (DED). METHODS: MSGs autotransplantations were performed in 18 eyes (17 patients) with severe DED. MSGFR were measured before operation. The upper or lower lip with higher MSGFR was selected as the donor site. Buccal mucosa was the back-up in cases labial MSGs showing markedly decreased MSGFRs. Two pieces of salivary lobules with the covering mucosa were harvested and transplanted to the recipient beds prepared in both upper and lower lids. RESULTS: The donor sites included lower lip in 12 eyes, upper lip in 5 eyes and buccal mucosa in 1 eye. Postoperative follow-up confirmed viable grafts in all cases. The overall subjective relief rate of DED symptoms was 58.8%, with Schirmer test values increasing from 0 mm to 4 mm (p<0.05). The mean preoperative MSGFR was 1.7 (range: 0.9–3.3) µL/min/cm(2). ROC analysis indicated an outstanding discrimination power for preoperative MSGFR to predicate postoperative relief of DED symptoms (area under the curve (AUC)=0.948, p<0.01). The maximum sensitivity (100%) and specificity (72.7%) were reached at a cut-off of 1.785 µL/min/cm(2). Patients with preoperative MSGFR >1.785 µL/min/cm(2) showed greater improvement of Schirmer test values after surgery than those with MSGFR ≤1.785 µL/min/cm(2) (p<0.05). CONCLUSION: MSGs transplantation proved to be useful for treating severe DED. The amount of postoperative lubrication and the treatment effect were positively correlated with preoperative MSGFR. MSGFR measurement and donor-site selection should be critical steps before the operation.